Safety-percussion cap responsive to rotation

ABSTRACT

A safety-percussion cap responsive to rotation which comprises a rotor capable of being set up in firing position and including locking means movable by centrifugal force and capable of being put out of engagement with the rotor. Bearing plates carry the rotor. The locking means include swingably locking bolts disposed on both sides of the rotor. The locking bolts engage the bearing plates. The locking bolts have a locking pin and a holding pin and are disposed each parallel to the axis of the rotor and operatively engage the rotor. They have additionally a spring including a worm toothing, and a spring causes the set up of the rotor.

nited States Patent Petzsch et al. 1 Jan. 23, 1973 [54] SAFETY-PERCUSSION CAP 2,546,999 4/1951 Graumann et al ..l02/79 RESPQNSIVE o ROTATION 2,748,707 6/1956 Graumann ..lO2/79 [75] Inventors: Lothar Petzsch, Langst-Kierst; primary gxan'liner samuel w EngIe Hans-Dieter Harnflu, Hass- Attorney-Ernest G. Montague linghausen, both of Germany [73] Assignee: Rheinmetall Gmbl-l, Dusseldorf, [57] ABSTRACT Germany A safety-percussion cap responsive to rotation which [22] Filed. Oct. 28,1970 comprises a rotor capable of being set up in firing position and including locking means movable by cenpp 84,594 trifugal force and capable of being put out of engagement with the rotor. Bearing plates carry the rotor. The locking means include swingably locking bolts F l P t [30] orelgn App canon y Data disposed on both sides of the rotor. The locking bolts Nov. 6, 1969 Germany ..P 19 55 812.4 engage the bearing plates. The locking bolts have a locking pin and a holding pin and are disposed each [52] US. Cl ..l02/79, 102/83 parallel to the axis of the rotor and operatively engage [51] Int. Cl. ..F42c 15/22 the rotor. They have additionally a spring including a [58] Field of Search ..l02/79, 80, '76, 83 worm toothing, and a spring causes the set up of the rotor.

[56] References Cited 8 Claims, 5 Drawing Figures UNlTED STATES PATENTS 2,789,507 4/l957 Apotheloz ..lO2/8O 2 .fi 1 26 21- 12 4 l/ S l9 S I t h 5 i lld t r- I I '1 3 2L 22 Z Z 24 i 31 28 -29 i.

PATENTEDJAH 23 I973 3.712.231"

SHEET 1 [1F 2 PATENTED JAN 2 3 I975 SHEET 2 OF 2 SAFETY-PERCUSSION CAP RESPONSIVE TO ROTATION The present invention relates to a safety-percussion cap which is responsive to rotation and which comprises a rotor set up in firing position, which rotor is retained in a safety position by means controlled by centrifugal forces.

in a known percussion fuse for twisted shells, the safety-percussion cap comprises a rotor capable of being set up into the firing position. This rotor is retained in safety position such, that it has a supporting face disposed cross-wise to the fuse axis, which supporting face is provided as engagement for movable locking bodies of a locking device, capable of being brought out of engagement with the rotor. The locking bodies themselves are equipped with movable releasing members securing the locking bodies against displacement in the transporting position for the release of the rotor locking, which releasing members, as well as the locking bodies, respond only upon effecting the centrifugal force successively and, thereby, free the rotor for setting up which is joined merely by friction.

In the known rotor, the center of gravity is chosen such, that it obtains a setting movement, whereby it assumes the firing position automatically and spontaneously upon release by the locking bodies and the releasing members. Substantially each of the known rotors is equipped with this setting movement.

With the exception of the low retarding effect by the locking bodies and releasing members responding next to each other, no further retardation takes place. This has the consequence, that a safety-percussion cap equipped with this locking body is characterized only by a very low forward barrel safety.

The above-mentioned known safety-percussion cap has been improved for this reason in the direction, that upon firing a safety element is upset, thus is shortened, whereby upon termination of the acceleration phase locking bodies are lifted under the influence of a centrifugal force from the rotor supporting face, whereby they grip simultaneously below the shoulders of the firing pin and lift the latter likewise so far, until the locking bodies have arrived outside of the shoulder. By this arrangement the rotor can now be set up into the ignition position due to its set up moment. These different measures require a plurality of construction elements with a very high measuring exactness. Aside from the fact that the production of such safety-percussion caps is time consuming and expensive, such complicated mechanisms can be produced economically only up to a certain size order from which, however, the firing pin for small caliber bullets or rockets are excluded.

It is one object of the present invention to provide a safety-percussion cap which is characterized by a rotor locking which is comparatively simple relative to its structure, as well as by an additional driving-and retarding-device assuming the up-sctting of the rotor into the ignition position.

It is another object of the present invention to provide a safety-percussion cap wherein the rotor is equipped with locking bolts swingable on both sides of the rotor from the outside against bearing plates, carrying the rotor, with a locking-pin and a holding-pin entering the rotor and disposed each parallel to the rotor axis and in addition having a spring causing the retarding upsetting of the rotor by means ofa worm toothing.

With this safety-percussion cap consisting comparatively of a few parts, a highest measure of safety is obtained against all other influences, as by centrifugal force, as can be ascertained from the following detailed statements.

Thus, in accordance with the present invention, each locking bolt is equipped with a passing through swinging axle, swingably guided between bearing supports, the swinging point of the locking bolt being chosen such, that the locking bolt obtains a closing moment by displacement of the center of gravity into the vicinity of the rotation axis during the firing-and accelerationphase, which moment is supported in addition by a blade spring effecting from the outside the locking bolt.

Both the locking-and holding-pins are disposed opposite each other relative to the rotor shaft, which is formed as a hollow shaft and enter recesses of this shaft and thereby enter the rotor.

A particular safety of the locking bolt results by the fact, that the locking-pin opposite the center of rotation is retained by means of the locking bolt on both sides extending by a weak blade spring, whereby the parts of the locking-pin entering into the recess are subjected to a locking preventing the swinging out of the locking bolt by engagement with the bearing plate.

In addition to the locking the safety-percussion cap contains otherwise effective from the outside with retardation for upsetting the rotor. The device comprises a spiral or helical spring, the spring force of which is produced by winding over a worm shaft and a worm pinion drives a worm wheel rim sitting on the rotor.

The helical spring is thereby secured on the inside at one end of the worm shaft, while the other end, accessible from the outside in the open bore of a bearing disc is equipped with a slot for winding the helical spring.

The parts consisting of rotor, lock, set up spring and retarding device are combined in a structural group closed by itself, which group is equipped with connections for insertion in mechanical or electrical head or bottom-fuses of twist-stabilized bullets and rockets.

In this safety-percussion cap consisting of comparatively few parts, the following functions are combined to the smallest space: The safety of the rotors against any mechanical influence except by centrifugal force, the upsetting of the rotor into the firing position by a force effective thereon from the outside and a retarding element disposed between the set up force and the ro tor.

With these and other objects in view, which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawings, in which:

FIG. 1 is a longitudinal section ofa safety-percussion cap with secured rotor designed in accordance with the present invention, along the lines l-l of FlG. 4;

FIG. 2 is a longitudinal section of the safety-percussion cap with secured rotor and partly an elevation along the lines llIl of FIG. I;

FIG. 2a is a longitudinal section of a fragmentary showing of the safety-percussion cap along the ,lines lla-lla of FIG. 2;

FIG. 3 is a longitudinal section with upright rotor in firing position along the lines lll-lll of FIG. 1; and

FIG. 4 is a top plan view of the safety-percussion cap upon removal of the fuse part receiving the percussion cap.

Referring now to the drawings, the device designed in accordance with the present invention comprises a cylindrical housing open at the bottom and at the top and receiving a bottom part 2, which serves the reception of two upright and parallelly disposed bearing plates 3. The latter are releasably connected together in turn by means of distancing bushings 4 and screws 5 exactly to the distance. The bearing plates 3 are equipped with covered bores 6, in which the two short rotor shafts 8 carrying the rotor 7 are easily rotatably mounted. The latter are formed as hollow shafts, and annular end faces of which extending flush with the outer face of the bearing plates 3, have two recesses 9 and 10 disposed diametrically relative to each other, of which the recess 9 is about double in width than the recess 10.

Perpendicularly to the rotor axis, a passing through bore passes the rotor 7, which bore is filled up with one or a plurality of primers 11.

Close to the one bearing plate 3 sits rigidly on the rotor 7 a worm wheel rim 12, which is in mesh with a worm pinion 13. The worm shaft 14 carrying the worm pinion 13 extends parallel to the axis of the fuse and sits with its one end in the open core of a bearing disc connecting the two bearing plates 3. The worm shaft 14 is equipped with a slot 16, which is accessible by means of a key or a screw driver through the bore of the bearing disc 15. The other end of the worm shaft 14 disposed opposite the slot 16, is connected with the inner end of a helical spring 17, the outer end of which is secured to the inner wall of the cage 18. Since the spring force of the helical spring 17 serves as driving source for the rotor 7, it must be wound by rotating the worm shaft 14, until it forms a compact spring package engaging tightly the worm shaft 14. A radial pin 19 projects on the jacket face of the rotor, which abuts upon upsetting the rotor 7 on an abutment pin 20 and thereby fixes the firing position of the rotor 7.

Outside of the rotor 7, and in particular engaging the outer wall of both bearing plates 3 is provided a locking bolt 21 with a passing through axis 22 between bearing supports 23. The swinging point 22, coinciding with the axis 22, is disposed in the neighborhood of the bottom part 2 and remote from the baring plate 3, whereby the locking bolt 21 has a center of gravity S in the vicinity of the rotating axis, whereby the locking bolt obtains a closing moment during the firing and accelerationphase, which moment is still effectively supported by a blade spring 24 effective from the outside.

ln the locking bolt 21 are inserted parallel to the rotor are each a locking-pin 25 and a holding-pin 26, whereby the locking'pin 25 disposed remote from the center of gravity S projects from both sides of the locking bolt 21, is retained from the outside by means of a weak blade spring 27 and on the inside enters into the broad recess 9 of the rotor shaft 8. The thin holding-pin 26 sits in a blind bore of the locking bolt 21 and enters the small recess 10 of the rotor shaft 8.

Both blade springs 24 and 27 are retained with their vertical arms by a filling member 34, which supports itself, on the one hand, by the blade springs 24 and 27 against the cylindrical inner wall of the housing 1 and, on the other hand, against the bearing support 23.

The housing 1 surrounding the entire inner device of the safety-percussion cap is a structural part closed in itself and equipped with connections 28 and 30, of which the connection 28 carries the housing 29, which contains the means releasing the firing and transmitting, respectively. These means can be in case of a mechanical fuse the striker and in case of an electric fuse a ram-like pin 31, which is put under tension by a current source against the central contact 11a embedded in the primer 11.

The other connection 30 receives the axial percussion cap housing 32 with the percussion cap 33. which is in direct connection with the percussion charge.

The safety-percussion cap operates during the transport in case of mechanical stresses, which take place in case of a lateral jolt cross-wise to the shell axis, so that at a maximum a locking-pin 25 emerges against the slight pressure of the blade spring 27 from the recess 9. The oppositely disposed locking-pin 25 is pushed in by the latter, however, still more than until now into a recess 9.

In the case that the safety-percussion cap is disposed in a bottom fuse, the locking bolt 21 would receive an opening moment if the shell falls down on the floor with its point, by the arrangement of the center of gravity S and the swinging point 22. The swinging out of the locking bolt 21 is, however, prevented such, that the inwardly projecting locking-pins are retained by the edges of the bearing plates 3.

The operation of the safety-percussion cap takes place as follows:

Under the effect of the axial acceleration occurring during firing and prevailing relative to the centrifugal force, the total inner device remains in rest position in accordance with FIG. 1. Only within the range of the muzzle, the acceleration is lowered so far, that the axial forces effective upon the inner device are reduced and can be more and more effective by the centrifugal forces caused by the shell twist. By this arrangement at first both locking-pins 25 are moved outwardly so far against the force of the weak blade springs 27, that they emerge from the recesses 9. On the other hand, the stronger blade springs 24, which engage from the outside the locking bolts 21, are arranged such that they retain the locking bolts 21 still in closing position, whereby the holding-pins 26 block still the rotor 7, by engagement in the recesses 10. Only at the muzzle overpass the centrifugal forces effective upon the center of gravity S of the locking bolt 21, so that both locking bolts 21 swing out from the resting position and then only towards the end of the swinging movement the rotor 7 is freed by the holding-pin 26.

The release of the rotor 7 is a presumption for the fact, that the wound helical spring 17 can now he released, whereby it drives by means of the worm shaft 14 and the worm pinion 13, the worm wheel rim 12 sitting on the rotor 7 so far, until the radial pin 19 engages the abutment pin 20. The position shown in FIG. 3 is assumed by the rotor 7 in view of the retarding effeet by the holding-pin 26 and the worm drive only, after the shell has safely left the muzzle with a few meters distance.

In this position, the contact pin 31 is pressed towards the central contact 11a of the primer 11, that means, it is now connected with the fusion circuit electrically conducting. Upon impact of the shell, the electrical energy is switched to the primer 11 such, that it is ignited and thereby, the ignition of the percussion cap 33 is started.

in case of a mechanical ignition a striker replaces the electric contact pin 31, which is joined upon arrival of the shell by a ram 35 rushing forwardly in the housing 29 and impinges thereby the primer ll projecting up to the periphery of the rotor housing 7, which primer 11 starts in turn the ignition of the percussion cap 33.

While I have disclosed one embodiment of the present invention, it is to be understood that this embodiment is given by example only and not in a limiting sense.

I claim: 1. A safety-percussion cap responsive to rotation comprising a rotor means capable of being moved to a firing position, locking means for locking said rotor and movable by centrifugal force and capable of being moved out of locking engagement with said rotor, bearing plates carrying said rotor, said locking means including pivotally mounted locking bolt means disposed on both sides, respectively, of said rotor and mounted for pivoting caused by centrifugal force, said locking bolt means engaging said bearing plates, said locking bolt means having a locking pin and a holding pin disposed therein each parallel to the axis of said rotor and operatively releasably locking said rotor against rotation, said locking pin and said holding pin disposed relative to the pivotal mounting of said locking bolt means such that said locking pin and said holding pin become operative to release said rotor for rotating, one after the other, and a worm gear operatively connected to said rotor, and a spring means operatively connected to said worm gear for turning the latter when said pins release said rotor. 2. The safety-percussion cap, as set forth in claim 1, wherein each of said locking bolt means is pivotally guided with an axle passing therethrough and between bearing supports, and the center of gravity being chosen such, that said locking bolt means are equipped with a closing moment by displacement of said center of gravity into the vicinity of the axis of rotation of said locking bolt means during firing and acceleration phase. 3. The safety-percussion cap, as set forth in claim 2, which includes a blade spring means engaging from the outside and effecting said locking bolt means for supporting the closing moment of said locking bolt means. 4. The safety-percussion cap, as set forth in claim 1, wherein said rotor includes a rotor shaft comprising a hollow shaft having diametrically oppositely disposed recesses, and said locking-pins and said holding-pins being operatively received in said recesses.

5. The safety-percussion cap, as set forth in claim 4,

which includes a weak blade spring retaining from the outside said locking-pin disposed remote from said axis projecting on both sides from said locking-pins, and

the portion of said locking-pins entering the cor-' responding of said recesses is locked preventing a swinging of said locking pin by engagement of the edge of the corresponding bearing plate.

6. The safety-percussion cap, as set forth in claim 1,

which includes said spring means comprises a tensioned helical spring,

a worm shaft having thereon a worm pinion,

said worm gear comprises a worm wheel rim on said rotor and driven by said worm pinion,

an abutment pin immovably fixed to said rotor,

a radial pin projecting from said rotor adapted to en gage said abutment pin upon turning of said rotor, in order to fix the firing position by a stroke movement of said radial pin relative to said immovable abutment pin.

7. The safety-percussion cap, as set forth in claim 6,

wherein one end of said helical spring is secured on the inside at one end of said worm shaft,

said worm shaft has a slot,

said bearing plate having an open bore, and

the other end of said helical spring accessible from the outside in the open bore of said bearing plate is adapted for winding said helical-spring by said slot of said worm shaft.

8. The safety-percussion cap, as set forth in claim 1,

comprising a closed structural unit, and

joining connections disposed on both sides of said unit adapted for connections with a fuse. 

1. A safety-percussion cap responsive to rotation comprising a rotor means capable of being moved to a firing position, locking means for locking said rotor and movable by centrifugal force and capable of being moved out of locking engagement with said rotor, bearing plates carrying said rotor, said locking means including pivotally mounted locking bolt means disposed on both sides, respectively, of said rotor and mounted for pivoting caused by centrifugal force, said locking bolt means engaging said bearing plates, said locking bolt means having a locking pin and a holding pin disposed therein each parallel to the axis of said rotor and operatively releasably locking said rotor against rotation, said locking pin and said holding pin disposed relative to the pivotal mounting of said locking bolt means such that said locking pin and said holding pin become operative to release said rotor for rotating, one after the other, and a worm gear operatively connected to said rotor, and a spring means operatively connected to said worm gear for turning the latter when said pins release said rotor.
 2. The safety-percussion cap, as set forth in claim 1, wherein each of said locking bolt means is pivotally guided with an axle passing therethrough and between bearing supports, and the center of gravity being chosen such, that said locking bolt means are equipped with a closing moment by displacement of said center of gravity into the vicinity of the axis of rotation of said locking bolt means during firing and acceleration phase.
 3. The safety-percussion cap, as set forth in claim 2, which includes a blade spring means engaging from the outside and effecting said locking bolt means for supporting the closing moment of said locking bolt means.
 4. The safety-percussion cap, as set forth in claim 1, wherein said rotor includes a rotor shaft comprising a hollow shaft having diametrically oppositely disposed recesses, and said locking-pins and said holding-pins being operatively received in said recesses.
 5. The safety-percussion cap, as set forth in claim 4, which includes a weak blade spring retaining from the outside said locking-pin disposed remote from said axis projecting on both sides from said locking-pins, and the portion of said locking-pins entering the corresponding of said recesses is locked preventing a swinging of said locking pin by engagement of the edge of the corresponding bearing plate.
 6. The safety-percussion cap, as set forth in claim 1, which includes said spring means comprises a tensioned helical spring, a worm shaft having thereon a worm pinion, said worm gear comprises a worm wheel rim on said rotor and driven by said worm pinion, an abutment pin immovably fixed to said rotor, a radial pin projecting from said rotor adapted to engage said abutment pin upon turning of said rotor, in order to fix the firing position by a stroke movement of said radial pin relative to said immovable abutment pin.
 7. The safety-percussion cap, as set forth in claim 6, wherein one end of said helical spring is secured on the inside at one end of said worm shaft, said worm shaft has a slot, said bearing plate having an open bore, and the other end of said helical spring accessible from the outside in the open bore of said bearing plate is adapted for winding said helical spring by said slot of said worm shaft.
 8. The safety-percussion cap, as set forth in claim 1, comprising a closed structural unit, and joining connections disposed on both sides of said unit adapted for connections with a fuse. 